PTPRZ1 and cardiac hypertrophy: Echocardiography analysis in mice identified that both systolic and diastolic functions are affected in <i>Ptprz1</i><sup>-/-</sup> compared with <i>Ptprz1</i><sup>+/+</sup> hearts, based on a dilated left ventricular (LV) cavity, decreased ejection fraction and fraction shortening, and increased angiogenesis in <i>Ptprz1</i><sup>-/-</sup> hearts, with no signs of cardiac hypertrophy.